Tree Spacing and the Hang You Can Actually Get

Most hang-angle advice is written as if you choose the angle first and the trees fall into line behind it. Standing at an actual campsite, it's the other way around: two trees exist exactly where they exist, and your job is to figure out whether they'll give you a comfortable, safe hang at all before you commit to hanging between them. That's a different question than "what angle am I hanging at," and it's the one our tree spacing calculator is built to answer.

Solving the geometry backward

Every other hammock hang calculator on this site starts from a tree distance you already have and works out an angle, a strap height, or a load. Tree spacing does the opposite: give it your hammock's ridgeline length and the strap height you can realistically reach on a trunk, and it tells you how far apart your two trees should be to land a comfortable 25–35° hang — before you've walked a single site looking for candidates.

That reordering matters because "how high can I comfortably reach and wrap a strap" is something you know about yourself in advance, while "how far apart are these two specific trees" is something you'd otherwise have to discover by trial, hang, and re-hang. Knowing your target distance range ahead of time turns campsite scouting from guesswork into a quick pace-off-and-check.

A worked example: reach height, 11-foot hammock

Take an 11-foot hammock on its standard 9.13-foot ridgeline (the usual 83% ratio), and run a range of realistic reachable strap heights — how high up a trunk you can comfortably wrap a strap while standing — through the actual calculator function:

• 4.5ft reach: recommended 10.39ft (range 9.13–12.86ft)
• 5.0ft reach: recommended 12.12ft (range 10.00–15.01ft)
• 5.5ft reach: recommended 13.85ft (range 11.43–17.15ft)
• 6.0ft reach: recommended 15.58ft (range 12.86–19.30ft)
• 6.5ft reach: recommended 17.32ft (range 14.29–21.44ft)
• 7.0ft reach: recommended 19.05ft (range 15.71–23.58ft)

Two things jump out. First, the relationship is linear — every extra six inches of reach buys you about a foot and three-quarters more tree distance at 30°. Second, a 5 to 6 foot reach lands on the "12 to 15 feet" figure that circulates as a hammock-camping rule of thumb. At a 4.5-foot reach the near edge of the range is the ridgeline itself: trees can never be closer together than the ridgeline is long, and if your reach would need them closer, the calculator says so instead of printing a distance.

Why a range instead of one number

The recommended distance targets your chosen angle exactly, but the min and max columns matter just as much, because real trees are never exactly where you'd plan them. The calculator builds in a ±5° tolerance band around the target angle — the max distance corresponds to a flatter edge of that band (never flatter than 20°, and rounded down), the min distance to a steeper edge — and reports both, precisely so you have room to work with instead of needing an exact figure to succeed.

In practice this means: if your candidate trees measure anywhere between the min and max distance for your reach height, you're in workable territory. Outside that range on the flat side, expect a noticeably flatter angle than you planned for — and remember that flatter angles don't just feel different, they load your straps harder for the same weight, which is covered in full in why a flatter hang multiplies the force on your straps.

When the trees you find don't cooperate

Not every site offers a pair of trees inside your ideal range, and you have a few honest options when that happens, roughly in order of how much they're worth trying first:

• Look a little further. A few extra minutes of walking often turns up a better-spaced pair than the first two trees you notice near the trail.
• Lower the straps for closer trees. Trees closer than the recommended distance are the easy case: attach the straps lower and the angle stays near 30°. Trees farther apart than the range are the hard case, because the fix people reach for, hanging lower and flatter, is the one that multiplies the load. Pick a closer pair instead.
• Accept the edge of the tolerance band, not past it. A hang at the flat or steep edge of the range is still workable; drifting well outside it is where you start trading real comfort and, on the flat side, real strap load.
• Recalculate with your actual strap height if you realize your first reach estimate was off — a foot of difference in how high you can comfortably wrap a strap moves the target distance by a meaningful amount, as the table above shows.

What you shouldn't do is force a hang between trees that are badly mismatched to your gear just because they're the only two nearby. A hang well outside the tolerance band is either uncomfortably steep and short, or flat enough to load your suspension far harder than it needs to be for no comfort benefit at all.

Spacing is only half the scouting job

Distance is a geometry problem, but which two trees you pick is a safety and stewardship problem, and it doesn't show up in any calculator output. A few things to check before you wrap a strap around anything, regardless of how perfect the spacing measures out:

• Live and healthy, not dead or dying. Leave No Trace’s hammock guide: “Do not hang your hammock from any dead trees. You could hurt yourself, as dead trees can be very hazardous.” The visual cues (missing bark, no canopy, obvious rot at the base) are usually apparent if you actually look before committing.
• Thick enough not to flex. A trunk that visibly bends or sways when you lean on it isn't a reliable anchor, whatever the spacing math says.
• No widowmakers overhead. A dead or broken branch caught in the canopy above your hang — a "widowmaker" — is a real hazard that has nothing to do with your suspension and everything to do with where you chose to sleep. Look up, not just at eye level, before you settle on a spot. Leave No Trace: “Even if your chosen tree looks alive, check above you for dead branches that could fall.”
• Wide, tree-friendly straps only. Whatever the spacing, use webbing straps rather than rope or cord — covered in depth in choosing tree-friendly straps — so the tree itself isn't damaged by a hang that was otherwise done right.

A field method without a tape measure

You won't always have a tape measure at a trailhead, and you don't need one. A normal adult stride is roughly 2.5 to 3 feet; pacing off heel-to-toe between two trees gets you within a foot or so of an accurate distance for most people once you've calibrated your own stride once against a known length at home. Alternatively, most hiking poles and many hammock ridgelines or straps have a known length printed or marked on them — laying one on the ground between the trees a couple of times is a quick, tool-free way to sanity-check a pace count. Neither method needs to be perfect; you're checking whether you're in the recommended range, not measuring for a contract.

Hammock length sets the floor, not the target

The worked example above used an 11-foot hammock, but because you sit at the middle of the span, the recommended distance comes from your reach and seat height, not your hammock: at a 5.5-foot reach it is 13.85 feet whether the ridgeline is the 11-footer's 9.13 feet or a 9-foot hammock's 7.47 feet. What the hammock changes is the floor (trees must be farther apart than the ridgeline is long, with room left for the suspension) and how long each side’s suspension has to be. A shorter hammock fits tighter pairs of trees; it does not need a different target distance.

What if your reach isn't the same on both trees?

Real trees aren't always the same shape, and it's common to be able to reach comfortably higher on one trunk than the other — a slight lean, a low branch in the way, a wider trunk that's awkward to wrap. The calculator's single reach-height input assumes both sides are attached at the same height, which is the setup that actually produces a level hammock. If one side is genuinely more restricted, use the lower of your two reach heights as the input for both, rather than the higher one. That keeps your calculated distance conservative and your hang level, at the small cost of possibly hanging a little lower on the more generous side than you strictly needed to.

Calibrate your own reach once

"Reachable strap height" is specific to you, not a fixed number, and it's worth measuring properly one time rather than guessing at every trip. Stand at a doorframe or a wall, reach up as if wrapping a strap around a trunk at a comfortable, sustainable height — not a maximum stretch you couldn't hold while also managing webbing and a buckle — and mark or measure that spot. Do this once at home with a tape measure and you'll have an accurate number to plug into the calculator for every future trip, instead of re-guessing under time pressure at a campsite with the light fading.

Making spacing work for you, not against you

The broader point is that tree spacing isn't an obstacle to plan around after the fact — it's the actual constraint your whole hang is built on, upstream of angle, sag, and load. Know your reach height and ridgeline length before you go looking, carry the recommended range in your head (or on your phone), and site-scouting turns into a quick pace-and-check instead of a hopeful guess followed by an uncomfortable night.